The present invention relates to a method for manufacturing a medical glass container with less generation of a crack.
As raw materials of a medical glass container, such as a medical vial, borosilicate glass excellent in chemical durability has been used in many cases. By heating and deforming a glass tube containing borosilicate glass, a mouth portion and a bottom portion of a vial are molded. When the borosilicate glass is heated, alkaline components contained in the borosilicate glass are volatilized. The volatilized alkaline components condense particularly on the inner surface near the bottom portion of the vial to generate a region deteriorated by processing. Such a region deteriorated by processing has a possibility of causing the elution of the alkaline components into a pharmaceutical agent and the like to be stored in the vial. To address the problem, the alkaline component elution standard is established in ISO4802-1 or ISO4802-2 and the like.
As a method for reducing the elution of alkaline components, a method is known which includes subjecting a deteriorated glass generated in the inner surface of a vial molded from a glass tube to fire blasting with an oxygen-gas flame by a point burner while rotating the vial (Patent Literatures 1 and 2).